Celtic Sea water temperature
Celtic Sea, Ringaskiddy · Sea/Coast
The current water temperature at Celtic Sea is 15.8 °C (as of September 20, 2026, source: official monitoring networks).
The sea lags the air by weeks: the warmest water often arrives after the warmest days. Measured buoy values show this honestly.
Measurement series & statistics
This measurement series includes 1398 data points since July 22, 2026.
Lowest recorded value: 15.4 °C on September 18, 2026 · highest value: 21.5 °C on July 24, 2026.
In September, temperatures have ranged between 15.4 °C and 19.1 °C.
The current value is 1.1 °C below the September average of this series.
Nearby waters
More measuring points: Celtic Sea
Frequently asked questions
Can you swim at Celtic Sea right now?
The current water temperature is 15.8 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Celtic Sea?
Currently 15.8 °C (updated continuously).
How warm is at Celtic Sea in September?
In September, the water temperature recently averaged 16.9 °C.
When is the water warmest at Celtic Sea?
Across the measurement record, July is on average the warmest month (19.6 °C).
